Zheng Fa slowly made his way to where Zhang was trapped.
When he arrived three zhang away, Zhang just happened to open her eyes.
Without a word exchanged, it was as if they'd met for a prearranged silent appointment.
Zheng Fa opened his "Topology" and continued teaching from where he had left off the previous day.
Sometimes, Zhang would interrupt him with questions about things she didn't understand.
Some of these were down to her incomplete knowledge, certain concepts eluded her, and Zheng Fa responded to those easily.
Others were things even Zheng Fa hadn't fully thought through, at which point he would find himself stumped by her questions.
He would frown and start to ponder.
Zhang wouldn't press him, just quietly watching him with a subtle smile on her lips.
Sometimes when Zheng Fa truly couldn't answer her questions, her smile contained a hint of smugness.
...
Both were cultivators, their thought processes far outpaced ordinary people.
